Carbureter.



. A. P. PLAUT. cmunmn.

APPLICATION FILED NOV. 4. I914.

Patented Nov. 14, 1916.

3 SHEETS-SHEET I.

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A. P. PLAU]. CARBURETER. pwuchnou FILED nov. 4. 1914'.

Patented Nov. 14-, 1916.

3 SHEETS-SHEET 2-' A. P. PLAUT.

CARBURETER.

APPI ICATION FILED NOV. 4. I914.

1,204,901. a w Patented Nov. 14, 1916.

3 SHEETS -SHEET 3- g/mm; 1 WWW vmm mom rnosrnn. main, or cLnvnLam), onto, assrenon or one-ms r mailmanv Specification of Letteis'llatent. I I

cnnnunnrnnl Application filed November 4, 1914. SerialN o. 876,280. I

residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Carbureters, of which the following is a) full, clear, and exact description.

- This invention is an improved carbureteradapted for use in connection with an internal combustion motor to produce the ex-' plosivecharges required b the motor.

. The principal 'objectof t e inventionis' to .produce substantial uniform mixture of air and fuel vapor of} any desired proportions under-all of thevarying conditions ."of use of the motonespeciallyon an automobile;

Another-object of the invention is to: produce' a carbureter. which "will render the starting of the motor easier.

- Another object is t o produce a cheap carbureter which will contain few parts, and

' none which use I The-invention is shown in the drawingsa nd, hereinafter described;- and definitely pointed out in .the appended claims.

. In the drawing Figuref lis a side eleva tion of a .carbureter embodying the 'inven tion in what is now believed-to be its best and simplest -form. .Fig. 2 is a. sectional plan view in'the .plane indicated by line A-JBon-'Fig. 3. Fig. 3 is a central vertical sectional view. of the carbureter' in the plane indicated by li-ne OD on Fig. 2. Fig. 4 is a. top plan view of the Venturi tubewhich is a part of the carbureteishown in-the pre-. .ceding figures. Fig.5 is-an elevation artly sectioned of an alternative form of t e in vention. Fig. '6 is a vertical sectional-view of the tubular body member anda'ssocia-te eil. parts showing *another modificatlon of the invention.- Fig-,7 is a side elevation of a part of the carbureter shown in Fi 5,de#

signed particularly to show the a nvalve -mechanism.' Figs. .8 and-9 are res eetivel sectional views in the planesgofl nes and G H on Fig. 7. 10 18 a.

sectional View in the plane of line J'K on the" .two air Fig. 10.

are liable to get out of order in 1 2 and 3, the tube 2 is a Venturi tube; and

the fuel expansion chamber is formed by means of a circumferentialgroove cut in the outer wall "of this tube. tion shownin Figs. 5 and 6 the tube 2 does Q89 not have the Venturi form, and the expansion chamberlies above an outwardly pro- I jecting flange 2 on the lower end of the tube The carburetor inelude's a body" "member 1 which may be flanged atits up per end to facilitate its connection .with the inlet manifold of the-motor; and when, in" use, this tubular body'member is open at its lower end for the admission of air; and in the'upper end of this tube is a throttle valve.

9 which may be of any suitable-form,- as, for example, abutterfly valve,fas shown. It is therein in the lane indicated byfthe line '11.-.11 found on Figs. 1 and 3 and 5 and 6.-

Patented Nov. 14,1916.

,one of. the'advantageous characteristics of I 'thisftubular, body that it contains no obstruct ons, such as a nozzle, to modify in an,

2 represents a'tubewhich isfitmd within the tube 1'; and .4 represents an annular expansion .izhamber between the two tubes 1- r and 2. In the construction shown in Figs.

In the construc- 2. As shown in Fig. 5this chamber has no top wall, while as shown in Fig.--6, there is a. top wall formed 'by the flange 2". In :all-

cases the outer wall of this annular chamber is formed by the outer. tubular body m'emberl. In open and unrestricted. communicatlon With'th s fuel reservoir is a nozzle 5 from which fuel is delivered into this annular expansion chamber.

'- The. several embodiments of the invention shown are eonstructed with special refer- .ence to making thestarting' of the-engine easy; and inorder tOIs'ecure'thisf-result, the

b'ottom of the expansion chamber and the discharge end of the nozzle '5 are-both'be- -low- .thej' fuel level,- as indicated by line 11'1'1'.As' a result of-this," when the en-' Igine is idle, some liquid fuel will flow into Fig, '7 and Fig. ll is a detached view of fand accumulate in the said expansion 'chamvalves which are also shown in ber. In the construction shownin l, s 2, 35nd 6 this nozzle communicates-dinectly- -v a with the annular expansion chamber. In

the construction shown in Fig. 5 the nozzle 5 discharges into a later'ally extended tube 4 which is in open communication with said annular expansion chamber, and is in' effect a part of it. In all cases this annular expansion chamber communicates freely in an upward direction with the interlor of the i tubular body member 1. In the constructionshown'in Figs. 1, 2 and 3, for example,

. there are a plurality otf small inclined holes 7 extending from the annular expansion chamber diagonally upward and inward through the wall of the Venturi tube,-their above but closely adjacent the most restricted part or throat of discharge ends being said Venturi tube. In the construction shown in Fig. 6 an" annular row of vertical holes 7 are formed through the flange 2 and it is through these holes that" communication is established upward from the annular expansion chamber to the tubular body member. In the construction shown in Fig.

;5 this upward communication between the device is in operation,communicates at its inner end with the annular expansion-chamber, and at 1ts outer end 1s in open communication with the atmosphere, at a point above the fuel level in the float chamber and annular expansion chamber. In each case, however, a valve is provided by which to vary the effective area of the inlet tothisair I tube. In the construction shown n Flgs'.

' seat.

1, 2, 3 and 6, a tubular valve 14 is screwed into the air tube, so that the most restricted area of the air passage will be always as great as the area of the hole 14 through this valve. The end 14 of the valve, however, is

made conical for engagement with a valve seat 6 within the air tube; and one or more holes 6" are made in the air tube above this" By unscrewingthe valve, it will be moved away I may be delivered into the annular chamber more or and its'seat. In the conmunicates at its upper end with the tubular valve chamber 15, in which, preferentially, there are two tubular valves 15, 17, hav ng "stems 16, 17, which respect vely pro ect, through opposite ends of'the valve chamber,

so that they maybe adjusted to any required position'.- lIn thewall of the valve chamber, forcooperation the valve :16, 1s a longs from its seat 6, so that there less extra air which enters theair [tube through said holes 6 and passes between the valve struction shown in Fig. 5- the air tube 6 com tudinally extended slot 15. In the'associated valve, 16 is a circumferential slot 16 of increasing width from one end to the other. By turning this-valve, the effective size of the air inlet tosaidvalve is increased ordiminished. In the valve-chamber 15 is also a circumferential slot 15', and in the associated valve 17 is another circumferential slot 17 By turningthe valve, one may increase or decrease the effective area of this slot,that is to say, the length of the open part thereof. It is not thought that two valvesfare necessary for varying the rate of flow of air through air tube 6 to the extent A necessary for practical purposes, but they may be used as shown. Both valves are tubular, and both communicate with the air tube 6 which discharges into the tube 4.

In constructing the described carbureter,

in any form, the expansion chamber 4 must be sufliciently large to enable the air enter ing the same, to break up and substantially atomize therein, the fuel also admitted to said chamber from nozzle 5. In a carbureter employing a Venturi tube as shown in Fig.

3, having a throat 11/16ths of an inch in diameter, this expansionv chamber will be large enough for the purposes, if it has a capacity of .2 cubic inches. In said carbureter the aggregate area of the holes 7 must be sufficient to allow the fuel and airfwhich are drawn into the expansion chamber to escape therefrom at the same rate. In practice it has been found that the aggregate area of these holes 7 should be about 23% of the area of the throat. It has also been found that entirely satisfactory results are attained if the combined area of the valve controlled in- ;lets to the air tube, when the valve v14: is wide open, is about 55% of the total area of the holes'7. These relative sizes have been chosen somewhat empirically, but as a result of considerable experiment, and with the particular view of permitting the use of a nozzle 5 having an opening large enough to insure that it may not be easily stopped up.

But having determined these relative sizes and having determined what the diameter of 'the throat'of the'Venturi tube should be to give the desired rate of velocity flow'through it for a particular engine with which it is to be used, one may calculate with sufficient ac-' curacy for practical purposes how large the nozzle opening should be to cause the device to produce under all the conditions of use,

a mixture having any desired proportion of air and atomized liquid fuel. For example, if it is desired to produce a 25 to 1 mixture, it must be remembered that'the degree of vacuum in the expansion chamber 4 is only 45% of the degree of vacuum in the throat of the Venturi tube. This is because the area of the inlet to the air tube is 55% of the total area of the holes '7, wherefore, since 55% of the air drawn from such holes is supplied by the air tube 6, the resulting vacuum in the expansion chamber must be 45% of that in the throat of the Venturi tube.

air, the air will flow 24.49 times as fast as said fuel; and if we wish to make a 25 to 1 mixture, we may use the. following formula to determine the relative area of the throat of the Venturi tube and the area of the fuel nozzle. X 600 X .45

That is to say, the area of the throat of the Venturi tube should be 275 times as great as the area of the hole through the nozzle.

. turi tube. Likewise fuelwill, be drawn from the nozzle into the expansion chamber at a definite rate, dependent upon the velocity of said air, or, more directly, upon the degree of vacuum in the expansion chamher, which, in turn, is dependent upon the velocity flow of the air in the Venturi tube and the relative areas of the holes 7 and the inlet to the air tube 6. Likewise air will rush with great rapidity into the expansion chamber, and will substantially atomize the fuel therein. The mixture of air and fuel spray will flow through the holes 7 and in flowingwill be more finely atomized, and will j oin and become thoroughly mixed with the air steamrushing through the Venturi tube. The proportions of air and fuel-spray will remain constant at all engine speeds and under all loads, because the proportioning conditions are'not changed by changes in the actual rate of flow of air through the Venturi tube.

It will be understood-that difl'erent grades of fuel and different atmospheric conditions will cause small indeterminablevariations in the values of some of the factors employed in calculation and will therefore cause some slight variations in the proportions ofthe ingredients of the explosive charges, but these may be compensated for, to the necessary ing the valve in the air tube.

The construction described is such also that when the engine is stopped there will be an accumulation of liquid fuel in the expansion chamber 4. When the engine is started, air rushing. into the expansion chamber will atomize and carry away with it at each suction stroke a considerable" quantity of this accumulated fuel thereb producing a very rlch mixture which wil facilitate thestarting-of the engine. In a very short-time, however, this accumulation of fuel willbe used up, and after this, the

carbureter will act normally, that-is in the If, the fuel is six hundred times heavier than practical degree, by adjust-f manner heretofore described. To facilitate the starting of the engine, a very light self I closin valve 19, as, for example the butterfiy Va ve shown, in Fig. 3 may be provided at the inlet end of the body tube. When the engine is idle, this valve will close.

When the engine is being started and is large part of the air which goes to the ena glue will come through the air tube 6 and the expansion" chamber. the engine has got to running normally, the

. vacuum in the body tube will be so great that this valve will occupy substantially the wide open position shown by dottedlines in Fig. 3. When the engine is idling this valve will be more or less closed, depending upon the rate at which the engine is running. This'will, of coursefchange the proportions of air and fuel, makin the mixture richer, but that is of no lmportance because, as soon'as the engine is running under any load, the self closing valve will be open; and so long as it is, the carbureter will furnish the explosive mixture of the desired pro ortions of fuel and air.

'Having d escribed my invention, I claim: 1. In a carbureter, the combination-of a tube which, except for the throttle valve hereinafter. mentioned, is normally unobstructed and is adapted for connection at its upper end with an in rnal combustion engine and contains a which is always in communication with the interior of said tube through one or more unclosable passageways a fuel: nozzle discharging into said annu ar chamber, a valve controlled air tube discharging into said annular chamber and a throttle valve in the first mentioned tube located well above the plane in which said passageways communicate with the interior of said tube;

2. In a carbureter, the combination of a body tube adapted for connection at its upper end'with an internal combustion engine, an unobstructed inner tube-fitted in said body tube,-there being between said tubes an annular chamber which communicates with the interior of said inner tube through an annular row of always open holes, a fuel nozzle discharging into said annular chamher, a valve-controlled air tube which at its inner end communicates with said chamber,- and a throttle valve in the body tube above said inner tube.

3. In a carbureter, the combination of a body tube adapted for connection at its upper end with an internal combustion engine,

annular chamber When, however,

an unobstructed ajutage fitted within said body tube, therebeing between said adjut- 21g? and .body tube an annular chamber w ich communicates with the interior of an unobstructed Venturi tube immovably said ajutage through a plurality of always open holes whose discharge ends are closely adjacent to the throat of said ajutage, a

fuel nozzle discharging into said annular chamber, a valve controlled air tube which discharges into said annular chamber, and. a throttle valve in the body tube above the ajutage. V

4. In a carbureter, the combination of a body tube adapted for connection at its upper end with an internal combustion engine,

fitted within said body tube and having in its outer periphery an annular groove which with a body tube forms an annular chamber, there being a plurality of always open holes leading from said chamber to the interior of said Venturi tube, and discharging into the same in 'a plane closely adjacent to the throat of said Ventun tube,

a fuel nozzle discharging into said annular chamber, and an air tube which communicates at its inner end with said annular chamber. a

5. In a carbureter, the combination with a constant level fuel reservoir, of a substantially vertical tube which is normally open at its lower end and is adapted for connection at its upper end with an internal combustion .engine and which contains in its wall a'chamber which is in open communication with the interior of said tube above the level of thefuel in said reservoir,-there being an open fuel duct connecting said chamber with said 'fuel reservoir, and an air tube which communicates at its inner end with said chamber and has its outer end above said fuel level,

6. In a carbureter, the combination of a constant fuel reservoir, a substantially vertical body tube which is open at the lower end and is adapted for connection at its upper end with an internal combustion en-.

glne, an inner tube fitted; within said body" tube, having in its outerflperipheryan annular groove which-forms with the body .tubean annular chamber whose Jgottom is "below the fuellevel in said reservoir, and which communicates with. the interior of slaidbody tubef ina plane above said fuel level, afuel nozzledischarging into said annularchamber in 1 a plane which "is be- I low thefuel level in said reservoir, and an 'air tube'whichcommunicates at its. inner, end withsaid annular chamber and has its "inlet opening above the. fuel level said :fuel reservoir.

j 7. Iu' a carburetenithe combination with .a constant level fuelreservoir, of a substan tially" vertical body tube which is open at its lower end, andis adapted forconhection at its upper'endfwith aninternal combustion motor, an inner tube fitted within said body tube,- there between said tubes an annular chamber, and there being a lurality of always open holes connecting said chamber with the interior of said inner tube in a plane above said -fuel level, and there being an open ductconnecting said 'fuel reservoir with said annular chamber,

and an air tube'which communicates at its inner end with said annular chamber and has its inlet opening above said fuel level.

8. In a carbureter, the combination with a constant level fuelreservoir, of a-subs'tantially vertical body tube which is open at its lower end, and is adapted for connection at its upper end with an internal combus tion motor, an ajhtage fitted within said ,-body tube, there being between said tube and ajutage an annular chamber, and there being a plurality of ducts connecting said chamber with-theinterior of said body tube in a planeabove said fuel level, and there being an open duct connecting said fuel reservoir with said. annular chamber, and a valve controlled air tube which communicates at its inner end with said fuel reservoir and has its inlet opening above said fuel level.

9. In a carbureter, the combination of a tubular body member, an ajutage "fitted. therein having in its outer surface an annular groove which forms with the body member an annular chamber, and having a" plurality of ducts through the wall of said and having a plurality of ducts extended obliquely downward from points within the 'ajutage just above the most restricted part of the throat thereof and communicating with said groove, an 'air tube communi eating at its inner end with sa d groove and extending therefrom at an inclination up- "ward and being open to the atmosphere, a

. float chamber arranged to maintai -1 the fuel level slightly belowthe most restricted partof the throat of the .ajutage, a ,fuel nozzle connected with said float chamber'and ex tending at an inclination upward through the wall of the body and having its inner end ,projected into the annular groove in the ajutage.

-' 11. In a carbureter, the combination of a tubular body formed with a chamber and 1 with an-open air tube, 311 ajutage fitted in said tubular body having an annular groove in its" outer surface, which, together with the tubular body forms an annular chamber withwhich said air tube communicates, there beingalso a series of ducts through the wall of the ajutage communicating with said annular chamberyafuel'nozzle which is secured in a hole in the wall of the body In testimony whereof, I hereunto afiix iny signature in the presence of two witnesses.-

' I ANTOINE. PROSPER PLAUT.

Witnesses:

E. L. THURSTON, L. I. PORTER. 

